Kellyn M. Hoffert, Raphaël J Durand, S. Gauthier
Jan 18, 2017
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0
Influential Citations
37
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Journal
European Journal of Organic Chemistry
Abstract
Eighteen push–pull pyrazine fluorophores are described. Methoxy, dimethylamino, and diphenylamino groups were used as electron-donating groups (EDGs), and six π-conjugated systems consisting of multiple bonds and 1,4-phenylene moieties were used to connect the EDGs to the pyrazine core. The chromophores were obtained by Knoevenagel condensation and palladium-catalyzed cross-coupling reactions starting from commercially available 2-methyl- or 2-chloropyrazine. The optical absorption and emission properties of these chromophores were studied in different solvents. Some proved to be highly emissive and exhibit strong emission solvatochromism, which suggests a highly polar emitting state, characteristic of compounds that undergo intramolecular charge transfer (ICT). The influences of the various electron-donating groups and π-conjugated systems on the emission and ICT have been carefully studied.